1. Field of the Invention
This invention relates to novel nonhydrophilic reactive monoazo dyestuffs. More specifically, it relates to reactive monoazo dyestuffs which dye polyester fibers, cellulose fibers or mixed fibers composed of polyester fibers and cellulose fibers in orange to red colors excellent in various fastness properties including light fastness.
2. Description of the Prior Art
Heretofore, there are known disperse mono- and bis-azo dyestuffs derived from 2-amino-4,5-dicyanoimidazoles and of the following general formula [A]: ##STR2## wherein R.sub.1 is alkyl, substituted alkyl or aralkyl; and A is a residue of a coupling component selected from the group consisting of:
(i) a 5- or 6-membered heterocyclic ring having an amino, oxo or hydroxy substituent, PA1 (ii) a substituted or unsubstituted napthol and PA1 (iii) an aromatic amine having no substituent at the 4-position to the amino group and having at least one aliphatic or alicyclic substitutent attached to said amino nitrogen (Japanese Patent Publication No. 17848/1977), and water insoluble monoazo dyestuffs containing no sulfonic acid group and of the following general formula [B]: ##STR3## wherein D represents an aromatic carbocyclic ring or an aromatic heterocyclic ring; R.sub.1 and R.sub.2 may be the same or different and each represents appropriately substituted alkyl, preferably alkyl having 1-4 carbon atoms in the alkyl chain; X represents halogen, especially chlorine, optionally substituted alkoxy or a group ##STR4## wherein R.sub.3 and R.sub.4 are hydrogen or the sme or different optionally substituted alkyl groups; Y represents appropriately substituted alkoxy or a group ##STR5## wherein R.sub.3 and R.sub.4 are as defined above (Japanese Patent Publication No. 36237/1970).
The dyestuffs [A] described in the aforesaid Japanese Patent Publication No. 17848/1977 are dicyanoimidazole type azo dyestuffs similar to the dyestuffs of this invention, but when cotton is dyed with said known dyestuff [A], since the dyestuff [A] has no reactive group, it does not easily dye cotton and further various fastness properties, such as wet fastness, e.g., washing fastness, water fastness etc., light fastness, abrasion fastness etc., are poor.
On the other hand, the dyestuffs [B] described in Japanese Patent Publication No. 36237/1970 are monoazo dyestuffs having a triazinyl group like the dyestuffs of this invention, but the triazinyl group in said known dyestuffs [B] is located in the coupling component in the dyestuff structure and no reactive group is present in the diazo component, whereas the dyestuffs of this invention have such a triazinyl group in the diazo component.
Thus, contrast to these known dyestuffs, the dyestuffs of this invention are reactive monoazo dyestuffs which are distinctly novel in the chemical structure.